diff --git a/Functions.md b/Functions.md
index 9476782..45794a8 100644
--- a/Functions.md
+++ b/Functions.md
@@ -21,7 +21,7 @@ function main(args) {
 exports.main = main;
 
 // You must explicitly specify where to find the function.
-AsyncFunction._filename = "program.js";
+AsyncFunction.__filename__ = "program.js";
 ```
 
 #### In the console